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Spinning
Dr. Mahesha H BAssociate Professor and Head
Department of Sericulture
Yuvaraja’s College,
University of Mysore, Mysuru, India
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Mounting & Spinning
Mounting:
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Mounting:
Picking the ripe worms and putting them on mountages is called 'mounting‘.
/
Transferring mature fifth instar larvae to mountages is called mounting.
Ripening of Worms
The silkworm loses appetite & stops eating
Skin becomes translucent in colour
Begins to look in search of a suitable place
worms move towards the periphery of the
Feeding worm
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worms move towards the periphery of the
rearing trays in search of anchorageRipe worm
SpinningAfter mounting, passes last excreta in semisolidcondition, & starts spinning.First forms Hammock
The movement of Head during spinningIn Outer Layer In Middle & Inner Layer
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Hammock i.e., FLOSS
MountingMethods of Mounting –
1. Hand Picking and Mounting
2. Straw Cocoonages in Japan
Revolving Mountages made of Cardboard3. Revolving Mountages made of Cardboard
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Mountages- Different types of mountages are used in different parts of India.
In addition to support the spinning worms, the mountages should satisfy the requirements like,
it provide convenient space of suitable dimension for spinning good sized cocoons,
should not promote formation of double cocoons, should not promote formation of double cocoons, malformed cocoons and flimsy cocoons,
should have provisions for drying up of the last excreta of the worm prior to spinning and prevention of its falling on the cocoons of other worms,
should be suitable for easy mounting and harvesting.
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Types Of Mountages- The common mountages are,
1. Bamboo Mountage: Chandrika which is formed by a
bamboo spiral is the most common mountage used in
South India and West Bengal. This consist of a bamboo mat
of size 1.8 m x 1.2 m supported by split bamboo reapers
on all sides. On this bamboo mat, a bamboo tape of 4 to 5
cm width is wound in a spiral manner. The bamboo tape
has V-shaped struts supported by three long bamboo has V-shaped struts supported by three long bamboo
strips. About 1000 -1100 worms can be mounted.
1.8 x 1.2 meters in sizeAccommodates 40 to 60 larvae per sq ftOr 1000-1100 larvae per chandrika
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2.Plastic corrugated mountage:
60 x 90 cms in size & accommodates with the regular trays
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3.Rotary Mountages:
Each mounting frame has 13 rows and 12
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Each mounting frame has 13 rows and 12 columns containing 156 mounting slots. Each slot is 4.5 x 3 x 3 cms in size and the dimension is 55 cms in length, 40 cms in width and 3 cms in depth.
4. Grass- Dried grass and twigs spread in shallow
bamboo baskets are used in Assam.
Dried weeds, paddy straw and fresh weeds are used
in Jammu and Kashmir. In these two moulting and
harvesting is difficult and require more labour.
Further, formation of double and deformed cocoons is high.
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Paddy GrassPaddy Grass
Mustard Hey
5. Bottlebrush Mountages
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Bottle brush mountage are not only cheap but can be fabricated very quickly and occupies very little space compared to Chandrika. It consists of a thick coconut or jute fiber-rope into which 6 to 9" sticks (midrib of coconut leaves) are inserted very closely. The silkworms used the sticks as support and spin the cocoons in the space between the sticks.
Population Density on Mountages
� 50 Worms per 30X30 cm Or 2 cm2 per worm
� Chandrike 1.8 X 1.2 m holds 1000-1100 worms.
� Revolving Mountages 1560 worms / unit
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Care During Mounting
Environmental Conditions
Temerature:
� Worms during spinning require a slightly higher
temperature than rearing.
� too high a temperature will compel the worms to
spin in haste and thus waste a lot of silk.
� Too low a temperature, causes delay in the spinning
and affects the colour, lustre and texture of cocoons.
Also, the cocoons will not be so compact.
� Too high a temperature make the filament thicker,
and too low a temperature, to make it thinner.
Violent fluctuation leads to ununiformity.
� Around 24°C is quite ideal for spinning.
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Care During Mounting continued….
Environmental Conditions
Relative Humidity:
� RH at the range of 60 to 70 per cent is ideal.
� Too much moisture affects the lusture of the filament.
� From the point of view of reeling, drier the air during
mounting the better it will be, but too great a dryness mounting the better it will be, but too great a dryness
debilitates the worms and is to be avoided.
� Ventilation is an essential point for attention as a good
deal of moisture has to be got rid of and there is also a
good deal of excreta-solid, liquid and gaseous.
� The practice in Karnataka and West Bengal to place
the chandrikes in the open has much in its favor.
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Harvesting� MV- Spinning Completes on 3rd to 4th day –
harvesting on 5th day
� BV- Spinning Completes on 4th to 5th day –
harvesting on 6th to 7th dayharvesting on 6th to 7th day
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Transportation
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Maintenance of Rearing Records
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Acknowledgements/References
to
1. Internet
2. Sericulture Manual II, FAO, Rome.
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